TY  - JOUR
A1  - Clarke, P.
T1  - When can group level clustering be ignored? Multilevel models versus single-level models with sparse data
Y1  - 2008
DO  - 10.1136/jech.2007.060798
JF  - Journal of Epidemiology and Community Health
VL  - 62
IS  - 8
SP  - 752
EP  - -758

ER  -